A little progress report:
I took @HuD 91gt's advice and centered up the manifold. All pipe lengths are equal as of now. The connection for the wastegates are 45 degree branches off the collecter with 90D ells welded to those.
I will be 3D scanning the borg warner tonight so I can create an autocad model of it. If anyone wants a Borg-Warner EFR 7670D autocad model, message me.
I am interested in a specific manifold design done by CRG Turbo Manifolds out of Australia. Here's a link and let me know what y'all think:

Awesome vid @seattlejester ! Inspired me to do this. See images.
So far...:
1: 19.75"
2: 19.75"
3: 19.375"
4: 21.75"
5: 21.625"
6: 21.5"
I will probably need to repipe all of it and especially runner 2 as this thing will put the turbo itself up wayyy to high. Will hit it again monday. I will have the engine in hopefully tomorrow and check clearances. I will also do a symmetric design including "prioritizing the wastegate" to show @HuD 91gt

If I have time this weekend, I will drop the engine in and take pics. I am able to take bunches and bunches of photos and process them into something called AGISoft Photoscan Pro. This creates a point cloud I can use to import the car and engine in 3D into autocad.
FYI, if this gets up and running like I want, I'll be investing all profits back into getting cool stuff like a liquid sand box. That way we can anneal and PWHT carbon steel pipe. Keep in mind, every manifold I design (with all of your help...credits will go where credit is due. Might finally donate to the website!) will undergo flow calculation and finite element modeling. All documentation will be provided along the way.

You are probably right about the welder. I'm a piper by trade and it's our job/duty to make welders hate us.
But seriously, I understand your statement about the turbine housing wastegate. I'm running a borgs warner EFR 7670 W/ 1.05 A/R twin scroll. I originally wanted the 0.92 A/R as it had an internal wastegate. Being that the 1.05 A/R is not available with an internal wastegate, I'm stuck using external. Poor planning on me? Maybe.
Is there a way we could give the wastegate a higher priority? I'm willing to make this as efficient and awesome as possible, while still being cheaper than a 6boost. Could you please please please explain to me how twin scroll is still effective in a waste gas scenario? The more I understand it, the better I could figure a work around/solution.
Quite honestly, because after much shopping around, I noticed the trend for S30 chassis to have a forward position turbo. However, I'm sure I could use a handy dandy search button to clarify this issue. If a center position turbo manifold will fit, I'd gladly re-work this and make it symmetrical! I'd imagine a symmetrical turbo would be easier to fabricate using mandrel bending as often as possible.
Thanks for your responses thus far. I'll do more work on this tomorrow.

Some background: I work at an engineering firm as a piping design specialist.
For those of you interested, I am designing a turbo manifold using my piping software at work. About a 3rd of the way complete. The photos don't show the wastegates, but I plan on utilizing two 38mm v-band waste gates. I plan on sending it to a fab shop and then installing it into my 75 280z. I use CADWorx 2018 and isogen. I will be sending the isometrics to an engineer in our process department to run flow calcs. I am working to make this manifold as efficient, equal length, and inexpensive as possible while trying to minimize the welds. Not saying it's going to be perfect...this is my first attempt at it. If I am able to produce a "Full Race" quality manifold for 1/4 the price, would there be a market for this?
On a personal note, I'll be jet coating the manifold and then wrapping it in two layers of 5mm thick pyrogel insulation. A buddy at the plants owes me big time and he's giving me a pony roll of pyrogel insulation.
Let me know your thoughts. I'm at the mercy of the forum! Have mercy on me!
Thanks,
Jeff

I pulled my engine and tranny last weekend while my kids and wife were out of town and now I want to restore my engine bay. I would like to know from those who have performed this swap what I can throw away. I would look at the photos of other peoples' engine bays who have performed the swap, but I'm not sure what has been hidden as opposed to demo'd/removed.
Please assume:
I will be keeping the AC system, relocating the battery to the back.
Thanks to everyone, I have been using this, my FSM, and youtube to help make a lot of this happen. In case you're wondering, my car came painted like this. I'll be dreaming up a new scheme either to match or something else.
Jeff
Engine Removed

Looking for an RB26DETT with the RWD conversion to install into my 75 280z. I will arrange shipping if needed. I can pick up if within 300 miles of Lake Charles, LA.
Must be in running condition with little rebuild needed. Harness is a must as well.
PM me if you have anything.

Info:
1975 280Z R200 diff non-LSD
Problem:
First of all, I made a mistake disassembling my suspension without first taking pictures...new to the weekend mechanic world...lots of forum searches, using my haynes manual, youtube, etc..
I have looked in my Haynes manual and searched google images of suspension breakdowns, and still can't seem to identify this part. If I remember correctly, I removed it from the differential mount area. I did lots of cleanup on it and was covered in oil/grime.
Please help! I attached pictures of the part.